PiRNA-independent Function of PIWIL1 as a Novel co-activator for Anaphase Promoting Complex/Cyclosome (APC/C) to Drive Pancreatic Cancer Metastasis
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA593186 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Piwi proteins are normally restricted in germ cells to suppress transposons through association with piRNAs, but are also frequently activated in many types of human cancers. Of great puzzle is the lack of induction of corresponding piRNAs in cancer cells, as we document here in human pancreatic ductal adenocarcinomas (PDAC), implying that such germline-specific proteins are somehow hijacked to promote tumorigenesis through different mode of action. To pursue the underlying mechanism, we now demonstrate that in the absence of piRNAs, the aberrantly induced human PIWIL1 in PDAC functions as an oncoprotein by activating the Anaphase Promoting Complex/Cyclosome (APC/C), which then targets a critical cell adhesion-related protein Pinin to enhance PDAC metastasis. This is in contrast to piRNA-dependent PIWIL1 ubiquitination and removal by APC/C during late spermiogenesis. These findings thus unveil an piRNA-dependent mechanism to switch PIWIL1 from a substrate in spermatids to a co-activator of APC/C in human cancer cells.
2020-02-01 | GSE141340 | GEO
Project description:In order to investigate the dynamic regulation of the APC/C by intrinsically disordered regions (IDRs) upon phosphorylation, we employed cross-linking mass spectrometry (CLMS). Given that the phosphorylation of Apc1-300L (IDR in Apc1) is a key determinant in its release from the co-activator binding site, we compared the interaction profiles of unphosphorylated and hyper-phosphorylated rAPC/C_WT complexes. The CLMS analysis highlights not only known interactions consistently identified within APC/C complexes, regardless of phosphorylation status, but also dynamic IDR-mediated interactions that are lost upon phosphorylation or are phosphorylation-dependent. Additionally, the data indicate that phosphorylation significantly reduces Apc1-300L's interaction with Apc8-L (IDR in Apc8) and Apc6, suggesting Apc1-300L's dislocation from the co-activator Cdc20 binding site, thereby facilitating Cdc20 loading onto the APC/C.
2024-04-23 | PXD050097 | Pride
Project description:Tissue development and homeostasis rely on the proliferation of progenitor cells, whose identities are established by tightly controlled gene expression networks. However, mRNA synthesis is inhibited during mitosis, and the transcriptional programs that define a cell type must be restarted upon entry into each new cell cycle; how this is accomplished is poorly understood. Here, we identified a ubiquitin-dependent mechanism that integrates gene expression with cell division to preserve cell identity. We found that WDR5 and TBP, which bind active promoters during interphase, recruit the E3 ligase anaphase-promoting complex (APC/C) to specific transcription start sites during mitosis. This allows the APC/C to locally decorate histones with K11/K48-linked ubiquitin chains, which destabilizes nucleosomes and ensures continued gene expression in the next cell cycle. Mitotic exit and transcription re-initiation are therefore controlled by the same essential regulator, the APC/C, which provides a robust mechanism to maintain cell identity through cell division.
2020-02-03 | GSE122298 | GEO
Project description:Cdh1p is one of the two substrate adaptor proteins of the anaphase promoting complex/cyclosome (APC/C), an ubiquitin ligase that regulates proteolysis during cell cycle. In this work, using a proteomic approach, we found 135 mitochondrial proteins whose abundance was significantly altered in the cdh1Δ mutant, with 43 up-regulated proteins and 92 down-regulated proteins. When considering the group of significantly up-regulated proteins, these included subunits of the mitochondrial respiratory chain, enzymes from the TCA cycle and regulators of mitochondrial organization, suggesting a metabolic remodelling towards an increase in mitochondrial respiration. In accordance, mitochondrial oxygen consumption and COX activity increased in the absence of Cdh1p. These effects seem to be mediated by the transcriptional activator Yap1p, a major regulator of the yeast oxidative stress response. YAP1 deletion suppressed the increased Cyc1p levels and mitochondrial respiration in cdh1Δ cells. In agreement, Yap1p is transcriptionally more active in cdh1Δ cells, and responsible for the cdh1Δ mutant higher oxidative stress tolerance. Overall, our results unveil a new role for APC/C-Cdh1p in the regulation of the mitochondrial metabolic remodelling trough Yap1p activity.
2023-02-24 | PXD039879 | Pride
Project description:Lactate is abundant in rapidly dividing cells, due to the requirement for elevated glucose catabolism to support proliferation. However, it is not known whether accumulated lactate affects the proliferative state. Here, we deploy a systematic approach to determine lactate-dependent regulation of proteins across the human proteome. From this data, we elucidate a mechanism of cell cycle regulation whereby accumulated lactate activates the anaphase promoting complex (APC/C). Remodeling of APC/C in this way is caused by direct inhibition of the SUMO protease SENP1 by lactate. We discover that accumulated lactate binds and inhibits SENP1 by forming a complex with zinc in the SENP1 active site. SENP1 inhibition by lactate stabilizes SUMOylation of two residues on APC4, which are required to reorient APC/C to allow UBE2C binding and thus increase APC/C activity. This direct regulation of APC/C by lactate is required to stimulate timed degradation of cell cycle proteins, and efficient mitotic exit in proliferative mammalian cells. The above mechanism is initiated upon mitotic entry when lactate abundance reaches its apex. In this way, accumulation of lactate communicates the consequences of a nutrient replete growth phase to stimulate timed opening of APC/C, cell division, and proliferation. Conversely, we show that aberrant remodeling of APC/C by lactate occurs when lactate concentrations are chronically elevated, which is a hallmark of numerous cancers. Moreover, persistent lactate accumulation overcomes anti-mitotic pharmacology to drive mitotic slippage via the newfound mode of APC/C activation. Taken together, we define a biochemical mechanism through which lactate directly regulates protein function to control cell cycle and proliferation.
2023-02-07 | PXD036641 | Pride
Project description:The development of drug resistant cancer is a chronic threat to those undergoing cancer treatment. Why cells develop resistance to drugs has been studied extensively, with many molecular mechanisms driving the process now understood, yet it remains a chronic problem with few treatment options. In this study we treated companion canines presenting to the Western College of Veterinary Medicine in Saskatoon with drug resistant lymphoma with adjunct metformin along with their normal chemotherapy. We obtained repeated tumor samples from 4 canines undergoing this therapy and assessed RNA obtained from these samples by microarray. We identified a highly interconnected 201 gene set upregulated in the 4 dogs that was associated with tumor progression. This gene set was enriched in genes involved in mitotic progression and chromosome maintenance. We observed that mRNAs encoding substrates of the Anaphase Promoting Complex (APC) were integral to this gene set. Treatment with metformin lowered both protein and RNA levels of these substrates, while relapse resulted in elevated levels once again. The change in APC substrates clearly reflects disease progression, indicating that APC activity is critical for cellular homeostasis and loss of this activity can result in tumor progression.
2018-12-01 | GSE121242 | GEO
Project description:Signal transduction by Small Ubiquitin-like Modifier (SUMO) regulates a myriad of nuclear processes. Here, we report on the role of SUMO in mitosis in human cell lines. Knocking down the SUMO conjugation machinery resulted in a delay in mitosis and defects in mitotic chromosome separation. Searching for relevant SUMOylated proteins in mitosis, we identified the APC/C complex, a master regulator of metaphase to anaphase transition, as a SUMO target. The APC4 subunit is the major SUMO target in the complex, containing SUMO acceptor lysines at positions 772 and 798. SUMOylation increased APC/C ubiquitylation activity towards a subset of its targets, including the newly identified target KIF18B. Intriguingly, SUMOylation of APC/C was regulated by casein kinase driven phosphorylation of serines at positions 777 and 779. Combined, our findings demonstrate the importance of SUMO signal transduction for genome integrity during mitotic progression and reveal a triad of PTMs, cooperating to drive mitosis.
2018-09-19 | PXD006335 | Pride
Project description:Tissue-specific transcriptional activity is silenced in mitotic cells but it remains unclear whether the mitotic regulatory machinery interacts with tissue-specific transcriptional programs. We show that such cross-talk involves the controlled interaction between core subunits of the anaphase-promoting complex (APC) and the ID2 substrate. The N-terminal region of ID2 bound to core APC subunits, which formed an ID2-compatible pocket that optimally oriented ID2 in the APC-CDH1 complex. Phosphorylation of serine-5 by CDK1 prevented the association of ID2 with core APC, impaired ubiquitylation and stabilized ID2 protein at the mitosis-G1 transition leading to inhibition of basic Helix-Loop-Helix (bHLH)-mediated transcription. The serine-5 phosphomimetic mutant of ID2 that inefficiently bound core APC remained stable during mitosis, delayed exit from mitosis and reloading of bHLH transcription factors on chromatin. It also locked cells into a “mitotic stem cell” transcriptional state resembling the pluripotent program of embryonic stem cells. The substrates of APC-CDH1 SKP2 and Cyclin B1 share with ID2 the phosphorylation-dependent, D-box-independent interaction with core APC. These results reveal a new layer of control of the mechanism by which substrates are recognized by APC.
2022-03-11 | GSE181639 | GEO
Project description:DNA double-strand breaks (DSBs) contribute to genome instability, a key feature of cancer. DSBs are mainly repaired by homologous recombination (HR) and non-homologous end-joining (NHEJ). We investigated the role of an isoform of the multifunctional cyclin-dependent kinase 9, CDK9-55, in DNA repair, by generating CDK9-55-knockout HeLa clones (through CRISPR-36 Cas9), which showed potential HR dysfunction. A phosphoproteomic screening in these clones treated with camptothecin revealed that CDC23 (cell division cycle 23), a component of the E3 ubiquitin ligase APC/C (anaphase-promoting complex/cyclosome), is a new substrate of CDK9-55, with S588 being its putative phosphorylation site. Mutated non-phosphorylatable CDC23(S588A) affected the repair pathway choice by impairing HR and favouring error prone NHEJ. Moreover, CDC23(S588A) promoted the ubiquitination of UFL1, a recently identified HR player. Overall, CDK9-55 could guide APC/C in choosing the correct DNA repair pathway, possibly by regulating UFL1 stability. This CDK9 role should be considered when designing CDK-inhibitor-based cancer therapies.
2021-07-20 | MSV000087856 | MassIVE
Project description:RNA-directed DNA methylation (RdDM) plays an essential role in transposable element (TE) silencing in plants. In the Arabidopsis RdDM pathway, the DDR complex containing DRD1, DMS3, and RDM1, is necessary for recruiting Pol V to transcribe scaffold RNA. Although the role of DDR is known, the mechanism by which the DDR complex is regulated remains unexplored. Here, we demonstrate that the Anaphase Promoting Complex/Cyclosome (APC/C) monitors the assembly of the DDR complex by targeting DMS3 for degradation. We show that a subset of Pol V-dependent RdDM loci are de-repressed in apc/c mutants, accompanied by defective recruitment and transcription of Pol V. APC/C targets DMS3 for ubiquitination and degradation in a D box-dependent manner, and the D-box-mutated DMS3 fails to complement the dms3 mutant. Competitive binding assays shows that the dosage of DMS3 is critical for the assembly of the DDR complex, and in vivo gel filtration analysis shows that the assembly of both DDR and Pol V is compromised in the apc8 mutant. These findings uncover a safeguard role of APC/C-mediated DMS3 degradation in the assembly of the DDR complex, and provide a direct link between selective protein degradation and RdDM.
2019-01-31 | GSE106970 | GEO